The Army Corps of Engineers will hire a contractor to redesign and replace intake valves at Russell Dam's eight turbines to prevent recurring leaks.
The nine-month project, estimated to cost $500,000 to $1 million, will include permanent closure of underwater intake valves for all eight turbines at the $570 million hydropower project, said corps spokesman Jim Parker.
The dam's current design includes eight separate intake valves that can be used to fill the penstocks that channel water into the turbines for use in generating electricity.
The redesign involves creating a single valve that can be used to fill all eight penstocks, which should eliminate the leak problems, Mr. Parker said.
"Right now there are eight individual valves used to fill the penstocks with water," he said. "We've had problems with those over the years in terms of leaking."
The problem likely is a design flaw, he said, and is unrelated to ongoing controversy over the dam's four reversible turbines, which pump water from Thurmond Lake back to Lake Russell for reuse in hydropower production.
The reversible technology boosts profits, but also is known to kill fish. The corps faces a lawsuit from the state of South Carolina and the National Wildlife Federation over whether the units can operate safely.
"This has nothing to do with the lawsuit," Mr. Parker said. "It's an operation and maintenance sort of thing. The leaking was of enough concern to us that we felt like there should be a different way to do it."
Such remodeling, he added, is not unusual with large hydropower projects, even those as new as Russell. "As you get experience with a relatively new structure, it's not unusual to determine there might be a better way to do something."
The dam was completed in 1983.
Bids on the project will be opened in January.